Current evolutionary theory posits that late dinosaurs were the closest ancestors of early birds. But just how flight evolved is a question still ruminating in the minds of scientists.
A study published September 18 in Nature Communications reveals evidence that feathered dinosaurs with archaic wing precursors could fly at low elevations- or rather, they could glide.
Scientists from the University of Southampton constructed an anatomically-accurate model of the 5-winged Cretaceous dinosaur Microraptor, who, 130 million years ago, had feathers on its forelimbs, legs, and tail. The researchers placed the model in a wind tunnel in order to simulate prehistoric sky conditions and determine if flight was in fact a possibility.
They found that Microraptor’s archaic wing shape and size was sufficient to allow for enough lift for flight. Microraptor would have glided slowly at at low elevations for short amount of time, scooping up small animals for quick mid-flight meals. But this mode of mobility wasn’t commonplace in Microraptors – they spent most of their time on the ground and climbing in trees.
The team believes that because a modern wing wasn’t necessary for aerodynamic gliding, the evolution of flight may have sprung up earlier. This research provided evidence against the counter theory that modern wing dimensions and proper location of forelimbs were necessary for flight. Fossils reflect a similar concept: the record of ancient remains shows evidence of gliding in early bird ancestors without morphologically modern wings.
Scientists at the university of Southampton created a model Microraptor that reflects the true proportions and feathers of the 130-million-year-old dinosaur who once glided Cretaceous skies.
The study authors also suggest that symmetric feathers, a feature of modern birds, evolved as a feature with uses other than for flight, but when flight was discovered, they came in handy and ultimately necessary for aerodynamic mobility. When this mode of travel became central, a more complex wing started to take the place of the archaic one, and modern birds stare taking to the skies on a regular basis.
Check out a video of the Microraptor wind tunnel experiments.
Find the Microraptor wind tunnel research study in the journal Nature Communications.
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